Who knew 17 years could go so fast? By the time it takes to send a kid to college, I’ve been toiling, mostly joyfully, at the Chronicle and SFGate.com. I am headed to KNBR 680-AM, where I will also be making radio appearances and occasionally filling in as a co-host and continuing as part of …

I offer this not to knock Smith, but to highlight a significant change since Kaepernick became the starter in 2012: The 49ers now have a big-play, quick-strike, scrare-the-bejeezus-out-of-defensive-coordinators offense. …

Tukuafu, 29, a defensive lineman, was inactive for the 49ers’ season-opening 34-28 win over the Packers. Signed to San Francisco’s practice squad in 2010, he appeared in 18 games over the past two seasons, playing 44 defensive snaps in 2012. …